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J C Horiot

Publications and source records attributed to J C Horiot.

At least 19 recordsLinked to original sources
PubMed2004

Conservative treatment of early glottic carcinomas with exclusive radiotherapy.

BACKGROUND: Early glottic carcinomas can be treated with radiotherapy or surgery with similar local control rates but with better functional results with radiotherapy. The aim of this study was to analyze the results of our experience of exclusive radiotherapy. PATIENTS AND METHODS: From 1975 to 2001, 155 patients with Tis, T1 and T2 glottic carcinomas were treated with exclusive radiotherapy. Prognostic factors of survival, local control and larynx-preservation rates were analyzed in uni and multivariate analyses. RESULTS: Median prescribed dose was 65 Gy in 44 days. Overall survival was 75% for the whole group, 75% for Tis, 85% for T1a, 72% for T1b, 59% for T2. Specific survival was 88% for the whole group, 75% for Tis, 94% for T1a, 90% for T1b, 69% for T2. Disease-free survival was 68% for the whole group, 75% for Tis, 77% for T1a, 51% for T1b, 58% for T2. Laryngeal preservation rate was 85% (133/155). Twenty-nine (29/155, 18%) patients developed a local relapse within 31 months. Out of the 10/86 (12%) T1a-Tis relapses, 7/10 patients underwent total laryngectomy and 79/86 larynx were preserved (92%). Out of the 8/22 (36%) T1b relapses, 4/8 patients underwent total laryngectomy. Out of the 11/47 (23%) T2 relapses, 8/11 patients underwent total laryngectomy. Increased overall treatment time, tumor stage, sub-glottis extension were associated with poorer local control. Second malignancies remain a major problem in the outcome of this population. CONCLUSION: Radiotherapy remains an efficient option in the treatment of early glottic carcinomas providing a high local control rate with excellent functional results in laryngectomy-free patients. This strategy should be discussed according to the tumor stage, feasibility of conservative surgery and patient's preferences.

Adult↗
PubMed2003

The Quality Assurance programme of the Radiotherapy Group of the European Organization for Research and Treatment of Cancer (EORTC): a critical appraisal of 20 years of continuous efforts.

In 1982, the European Organization for Research and Treatment of Cancer (EORTC) Radiotherapy Group established the Quality Assurance (QA) programme. During the past 20 years, QA procedures have become a major part of the activities of the group. The methodology and steps of the QA programme over the past 20 years are briefly described. Problems and conclusions arising from the results of the long-lasting QA programme in the EORTC radiotherapy group are discussed and emphasised. The EORTC radiotherapy group continues to lead QA in the European radiotherapy community. Future challenges and perspectives are proposed.

Clinical Trials as Topic↗
PubMed2002

Quality assurance in radiotherapy: from radiation physics to patient- and trial-oriented control procedures.

The stepwise process of the EORTC Quality Assurance Programme in Radiotherapy is described in function of two main criteria: the targets of the quality control procedures implemented, in Radiation Physics and clinical research, by the EORTC Radiotherapy Group and the development of both trial- and patient-oriented quality systems. This exhaustive program, which started in 1982, is characterised by three main periods. The first one was fully dedicated to pioneer steps in Radiation Physics measurements, on-site audits and inventories of human resources, staff workload and department infrastructure in institutions participating to EORTC trials. During the second period, which started in the late 1980s, a series of quality systems were implemented to test the compliance of the investigators to follow protocol guidelines, through the use of standard and uniform control procedures like the dummy runs, in order to tackle systematic errors in the participating institutions. Finally, the third period, which took place in the 1990s, was essentially patient-oriented, thanks to large scale individual case reviews, to check the validity of data recording and reporting processes and trace random errors throughout the radiotherapy treatments. Most of the results collected during these two decades allowed the implementation of well codified quality control procedures which, nowadays, can be used outside the field of clinical research, by national societies or bodies willing to improve treatment standards on a large scale.

Clinical Trials as Topic↗
PubMed2002

EORTC Radiotherapy Group: achievements and future projects. European Organisation for Research and Treatment of Cancer.

The European Organisation for Research and Treatment of Cancer (EORTC) Radiotherapy (RT) Group will celebrate 27 years of activity in 2002. During its long history, the Radiotherapy Group has conducted a large number of studies which have provided valuable information on the radiation treatment of several disease sites. Group efforts have been concentrated on dose-effect studies, optimal fractionation schemes, combinations with other treatment modalities, and new radiotherapy techniques. The EORTC RT Group was the first in Europe to develop and introduce methodologies of Quality Assurance in radiotherapy. The RT Group actively collaborates with other EORTC Groups and international organisations. Currently, several phase III studies are being conducted in collaboration with European, North American and Australian organisations. The collaboration with RTOG led to the setting up of common systems for scoring late normal tissue effects. In the years to come, the Group will keep pioneering pivotal trials in radiotherapy and radio-chemotherapy. It will also explore combinations with novel therapies in phase I trials and implement innovative translational research programmes.

Breast Neoplasms↗
PubMed2001

Recurrence rates after treatment of breast cancer with standard radiotherapy with or without additional radiation.

BACKGROUND: Radiotherapy prevents local recurrence of breast cancer after breast-conserving surgery. We evaluated the effect of a supplementary dose of radiation to the tumor bed on the rates of local recurrence among patients who received radiotherapy after breast-conserving surgery for early breast cancer. METHODS: After lumpectomy and axillary dissection, patients with stage I or II breast cancer received 50 Gy of radiation to the whole breast in 2-Gy fractions over a five-week period. Patients with a microscopically complete excision were randomly assigned to receive either no further local treatment (2657 patients) or an additional localized dose of 16 Gy, usually given in eight fractions by means of an external electron beam (2661 patients). RESULTS: During a median follow-up period of 5.1 years, local recurrences were observed in 182 of the 2657 patients in the standard-treatment group and 109 of the 2661 patients in the additional-radiation group. The five-year actuarial rates of local recurrence were 7.3 percent (95 percent confidence interval, 6.8 to 7.6 percent) and 4.3 percent (95 percent confidence interval, 3.8 to 4.7 percent), respectively (P<0.001), yielding a hazard ratio for local recurrence of 0.59 (99 percent confidence interval, 0.43 to 0.81) associated with an additional dose. Patients 40 years old or younger benefited most; at five years, their rate of local recurrence was 19.5 percent with standard treatment and 10.2 percent with additional radiation (hazard ratio, 0.46 [99 percent confidence interval, 0.23 to 0.89]; P=0.002). At five years in the age group 41 to 50 years old, no differences were found in rates of metastasis or overall survival (which were 87 and 91 percent, respectively). CONCLUSIONS: In patients with early breast cancer who undergo breast-conserving surgery and receive 50 Gy of radiation to the whole breast, an additional dose of 16 Gy of radiation to the tumor bed reduces the risk of local recurrence, especially in patients younger than 50 years of age.

Adult↗
PubMed2001

[Prevention of pelvic recurrence by preoperative radiochemotherapy and total mesorectal excision of rectal carcinoma?].

Preoperative radiotherapy (RT) alone or in combination with a pre- or postoperative chemotherapy reduces the recurrence rate and increases the survival rate for patients with resectable rectal cancer. The therapeutic index, i.e. relationship between effects and side effects is objective of studies. Especially toxicities to the small intestine and to the sphincter function are evaluated. Preoperative radiotherapy achieves the best results. The treatment volume includes the mesorectum in case of continence maintaining surgery and includes the anal sphincter in case of abdominoperineal resection. To exclude the small intestine from the RT-field, we prefer the use of 3 or 4 field technique in a prone position with filled bladder, using an optimal field limitation. The Swedish study, which uses 25 Gy in five fractions per week leads to an increased rate of acute and late toxicities. A fractionation schedule using 45-50 Gy in five weeks should be preferred. During the radiotherapy the patient is followed-up once per week. If surgery is foreseen, it should take place as soon as 3 weeks after the end of radiotherapy. If a primary surgery is performed preoperatively, the operative finding should be discussed with the surgeon. Quality control programs have to certify optimal treatment of the patient by radiotherapist and surgeon.

Chemotherapy, Adjuvant↗
PubMed2001

Postoperative pelvic radiotherapy with or without elective irradiation of para-aortic nodes and liver in rectal cancer patients. A controlled clinical trial of the EORTC Radiotherapy Group.

OBJECTIVE: The purpose of this randomized multicenter study was to assess the impact on disease free and overall survival of low dose irradiation to para-aortic nodes and liver in patients with a locally advanced resected rectal cancer receiving a 50 Gy postoperative pelvic radiotherapy. PATIENTS AND METHODS: Main inclusion criteria were: a curative resection for a histologically proved carcinoma of the rectum, Gunderson-Sosin stages B2-B3, C1-C3, age <70 years. The patients were randomized between pelvic irradiation (Lim-XRT): 50 Gy in 25 fractions over 5 weeks and extended irradiation (Ext-XRT): same scheme/doses in the pelvis and extended fields on para-aortic nodes and liver, delivering 25 Gy in 19 fractions over 25 days. From 1983 to 1992, 484 patients were enrolled by 18 EORTC institutions and 29 patients were ineligible. The end-points were local and distant relapses, toxicity and survival. RESULTS: Compliance to treatment: 87.2% in Lim-XRT arm and 71.8% in Ext-XRT arm. Moderate acute hematological and hepatic toxicities were significantly increased in Ext-XRT arm. Among 325 patients at risk, 44 suffered a severe intestinal complication requiring surgery in 29. The 5- and 10-year estimates of disease free survival were respectively 42 and 31% in Lim-XRT arm and 47 and 31% in Ext-XRT arm (ns). The corresponding figures for overall survival were respectively 45 and 40% in Lim-XRT arm and 48 and 37% in Ext-arm (ns). The 10 years estimate of intra-pelvic failures was approximately 30% in both arms. Patients in Ext-arm appeared to have a slight shorter interval free of liver metastases (P=0.047). CONCLUSION: Low dose irradiation to the para-aortic nodes and liver did not improve survival for patients with resected adenocarcinoma of the rectum.

Aorta, Abdominal↗
PubMed2001

[Secondary effects of brachytherapy in the treatment of coronary restenosis].

Brachytherapy is proposed for the treatment or prevention of coronary restenosis with encouraging results, especially in intra-stent restenosis. The results of the first clinical studies show benefit, for example those of the American SCRIPPS trial with a 3 year follow-up. However, recent reports in the literature have described secondary effects associated with this technique: 1) stenoses occurring at the limits of the irradiated segments which are attributed to a proliferative effect of low doses on damaged tissue; 2) late occlusions at the irradiated site: their incidence is estimated at 9% at 6 months. The mechanisms of these thromboses are not understood but delayed re-endothelialisation probably plays a rôle; 3) finally, irradiation is associated with uncovered dissection probably related to delayed healing. Other long-term trials are necessary to provide a more complete assessment of the secondary effects of brachytherapy, especially with regards to their mechanisms, prevention and treatment.

Angioplasty↗
PubMed2001

[Multicenter study on dose escalation with conformal and conventional radiotherapy for the treatment of localized prostatic cancer. Preliminary results of tolerance and quality of life].

OBJECTIVE: To study the safety of conformal radiotherapy dose escalation up to 80 Gy for curative treatment of prostate cancer. MATERIAL AND METHODS: A multicentre trial sponsored by the PHRC include 164 patients under the age of 75 years with stage T1b-T3 N0 M0 prostatic adenocarcinoma, between 1995 and 1998. The prostate was treated at 5 dose levels: 18 patients at 66 Gy, 28 at 70 Gy, 49 at 74 Gy, 48 at 78 Gy, 21 at 80 Gy. The acute and delayed toxicity was graded according to a multidisciplinary glossary. Quality of life was evaluated before and one year after treatment using the EORTC QLQ-C30 questionnaire and additional questions. RESULTS: 89% and 55% of mild or moderate gastrointestinal and urinary adverse effects were observed during treatment, respectively. At long-term follow-up, of the 162 evaluable patients, 12.3% presented grade 2 adverse effects and 2.5% presented grade 3 adverse effects (1 case of haematuria, 2 urethral strictures, 1 bladder neck lesion) with no significant difference between the various dose levels. Two successive quality of life questionnaires were available for 119 patients: tiredness, pain and dyspnoea increased in parallel, but non-significantly in the groups receiving conventional doses or high doses. The proportion of patients reporting sexual activity without endocrine therapy decreased from 48% before treatment to 35% one year later. The proportion of patients with no clinical or laboratory signs of progression was higher in the high-dose group. CONCLUSION: No significant difference was observed between conventional dose levels and high dose levels in terms of toxicity or quality of life. As the adverse effects were acceptable, a randomized trial comparing 70 Gy and 80 Gy has been initiated.

Adenocarcinoma↗
PubMed2000

Impact on treatment outcome and late effects of customized treatment planning in cervix carcinomas: baseline results to compare new strategies.

PURPOSE: The aim of the study was to determine the predictive factors of complications, to evaluate the impact of customized treatment planning on late normal tissue effects per stage, and to report disease-free survival (DFS) and local control (LC) rates. METHODS AND MATERIALS: From 1970 to 1994, 642 patients were treated with radiotherapy alone for carcinoma of the intact uterine cervix. According to the International Federation of Gynecology and Obstetrics (FIGO) substaging, 34% were Stage I, 39% Stage II, and 27% Stage III. The analysis was divided into three periods: 1970-1978 (use of standard prescriptions),1979-1984 (implementation of individual adjustments), 1985-1994 (systematic individual adjustments). Five-year DFS, LC, and complications rates were calculated using the Kaplan-Meier method. Predictive factors of complications were determined by univariate analysis using frequency tables and nonparametric t-tests. Multivariate analysis consisted of a polychotomous stepwise regression. RESULTS: The comparison of the three time periods showed a significant reduction of the external radiation dose (dose above 40 Gy in 47% of patients before 1979 vs. 36% after 1984), of the use of parametrial boost (55% vs. 39%), of the use of vaginal cylinder (28% vs. 11.5%), and of the HWT volume (combined intracavitary and external irradiation) (842 cc vs. 503 cc on average). The total sequelae/complications rate, all toxicity grades, all stages, all organs was 51%. Five-year actuarial rate per toxicity grade was: G1, 42%; G2, 23.5%; G3, 10%; G4, 3%. The three main predictive factors for rectal and bladder sequelae/complications (all toxicity grades) taking into account time period were: the increase of external radiation dose, the high dose rate at reference points, and the whole vagina brachytherapy. No G4 occurred in the third period. The rate of G3 complications dropped from 16% to 6% over time: from 5% during the first period to 0% during the third period in Stage I, from 8% to 6% in Stage II, and from 23% to 12% in Stage III. G3 currently describes a variety of clinical situations with a different impact on quality of life which justifies further refinements of definitions of late effects. In our experience the severity of G3 markedly decreased: less than one-third of G3 had a real impact on quality of life in the last period compared to more than two-thirds in the first period. Meanwhile, 5-year LC rates remained stable in Stages I and II, 91% and 85% respectively. Conversely they fell from 75% to 55% in Stage III, thus raising the problem of underdosage and/or more accurate staging with time. CONCLUSIONS: Customized treatment planning eradicated lethal complications and provided a significant decrease of G3 in all stages while maintaining high cure rates in early stages. Dose reduction should be considered with caution in Stage III.

Actuarial Analysis↗
PubMed2000

Preoperative radiochemotherapy in rectal cancer: long-term results of a phase II trial.

PURPOSE: To assess toxicity and long-term results of preoperative chemoradiotherapy in rectal cancer. METHODS AND MATERIALS: Between 1989 and 1997, as a phase II study, 66 patients with T3 M0, rectal cancer received preoperatively a 45 Gy dose pelvic radiotherapy (XRT) combined with two 5-day chemotherapy courses (CT) of 5-Fluorouracil (5-FU) and Leucovorin (LV) delivered the first and fifth week of XRT. For each CT course, LV:20 mg/m2/d1-d5,. While the 5-FU dose was variable from 450 to 350 mg/m2/d first course and 370 to 350 mg/m2/d second course. Surgery was planned 3 weeks later. RESULTS: XRT-CT was stopped in 1 patient due to progressive disease. CT was stopped in 1 patient due to toxicity. Grades 2 and 3 diarrhea were observed in 8 and 3 patients, respectively. One patient died from acute diarrhea due to deviation from recommendations; 60 patients went to surgery. Among the 58 patients operated on for cure, 5 had an R1-resection. After a 4.5-year median follow-up, the 5-year pelvic disease-free survival was 92% for the whole group and 96% in the R0-resection group. CONCLUSION: Preoperative combined XRT-5-FU-LV is feasible if optimal XRT and patients are carefully managed. The recommended 5-FU daily dose is 350 mg/m2 for both CT courses. This approach is currently tested in a large EORTC phase III trial.

Adult↗
PubMed2000

High dose rate brachytherapy for superficial cancer of the esophagus.

PURPOSE: We analyzed our experience with external radiotherapy, combined modality treatment, or HDR brachytherapy alone to limited esophageal cancers. METHODS AND MATERIALS: From 1991 to 1996, 25 patients with limited superficial esophagus carcinomas were treated by high dose rate brachytherapy. The mean age was 63 years (43-86 years). Five patients showed superficial local recurrence after external radiotherapy. Eleven patients without invasion of the basal membrane were staged as Tis. Fourteen patients with tumors involving the submucosa without spreading to the muscle were staged as T1. Treatment consisted of HDR brachytherapy alone in 13 patients, external radiotherapy and brachytherapy in 8 cases, and concomitant chemo- and radiotherapy in 4 cases. External beam radiation was administered to a total dose of 50 Gy using 2 Gy daily fractions in 5 weeks. In cases of HDR brachytherapy alone (13 patients), 6 applications were performed once a week. RESULTS: The mean follow-up is 31 months (range 24-96 months). Twelve patients received 2 applications and 13 patients received 6 applications. Twelve patients experienced a failure (48%), 11/12 located in the esophagus, all of them in the treated volume. One patient presented an isolated distant metastasis. In the patients treated for superficial recurrence, 4/5 were locally controlled (80%) by brachytherapy alone. After brachytherapy alone, 8/13 patients were controlled (61%). The mean disease-free survival is 14 months (1-36 months). Overall survival is 76% at 1 year, 37% at 2 years, and 14% at 3 years. Overall survival for Tis patients is 24% vs. 20% for T1 (p = 0.83). Overall survival for patients treated by HDR brachytherapy alone is 43%. One patient presented with a fistula with local failure after external radiotherapy and brachytherapy. Four stenosis were registered, two were diagnosed on barium swallowing without symptoms, and two required dilatations. CONCLUSION: High dose rate brachytherapy permits the treating of patients with superficial esophageal cancer with good tolerance. Early tumors, located in the mucosa, might be treated by HDR brachytherapy alone or by a combined modality treatment in which HDR brachytherapy can take place like a boost. This approach may cure localized recurrences.

Adenocarcinoma↗
PubMed2000

Post-radiation severe xerostomia relieved by pilocarpine: a prospective French cooperative study.

BACKGROUND AND PURPOSE: The aim of the study was: (1) to confirm the action of pilocarpine hydrochloride (Salagen) against xerostomia: (2) to correlate the response to dose/volume radiotherapy parameters. MATERIALS AND METHODS: From June 1995 to February 1996, 156 patients with severe radiation induced xerostomia received pilocarpine hydrochloride orally. IS mg per day with a 5 mg optional increase at S weeks up to a daily dose of 25 mg beyond 9 weeks. RESULTS: One hundred and forty five patients are fully evaluable. Treatment compliance was 75%. Thirty eight patients (26%) stopped treatment before week 12 for acute intolerance (sweating, nausea, vomiting) or no response. No severe complication occurred. Ninety ses en patients (67%) reported a significant relief of symptoms of xerostomia at 12 weeks. Within 12 weeks, the size of the subgroup ith normal food intake almost doubled (13-24 patients) while the size of the subgroup with (nearly) impossible solid food ingestion decreased by 38% (47 vs. 29 patients). The impact on quality of life was considered important or very important by 77% of the responders. CONCLUSIONS: No difference was found according to dose/volume radiotherapy parameters suggesting that oral pilocarpine hydrochloride: (1) acts primarily by stimulating minor salivary glands: (2) can be of benefit to patients suffering of severe xerostomia regardless of radiotherapy dose/volume parameters: (3) all responders are identified at 12 weeks.

Administration, Oral↗
PubMed2000

Radiotherapy of advanced mycosis fungoides: indications and results of total skin electron beam and photon beam irradiation.

BACKGROUND: The goals of this retrospective study of advanced mycosis fungoides are (1) to describe the indications of a combination of total skin electron beam and photon beam irradiation and (2) to analyze the results of total body or segmental photon irradiation for patients with extension beyond the skin. METHODS: From January 1975 to December 1995, 45 patients with pathologically-confirmed mycosis fungoides or Sézary syndrome received a combination of TSEB and photon beam irradiation for advanced disease: 34 males and 11 females, mean age 61 years (range 27-87 years). The mean follow-up was 111 months (range 18-244 months, median 85 months). Whole-skin irradiation treatment to a depth of 3-5 mm with a 6-MeV electron beam was produced by a linear accelerator to a total dose of 24-30 Gy in 8-15 fractions, 3-4 times a week. In cases of thick plaques or tumors that were beyond the scope of low energy electron beams or for treating nodal areas (especially in the head and neck area or axilla involvement), regional irradiation (RRT) with Co-60 photon beams was followed by whole-skin electron beam irradiation (15 patients). In cases of diffuse erythrodermia, Sézary syndrome, nodal or visceral involvement, total body irradiation was delivered with a 25-MV photon beam using a split-course regimen to prevent hematological toxicity (22 patients). The first course consisted of 1.25 Gy delivered in ten fractions and 10 days. Subsequently, patients received TSEB. Four to 6 weeks after TSEB, they received a second course of 1.25 Gy. The cumulative TBI dose ranged from 2.5 to 3 Gy in about 3 months. Hemi-body irradiation (HB) with Co-60 (and a bolus) was given in cases of multiple regional tumors with large and thick infiltration of the skin to a dose of 9-12 Gy (using fractions of 1-1.5 Gy/day) which, once flattened, were boosted with whole-skin electron beam therapy (8 patients). RESULTS: At 3 months, the overall response rate was 75% with 23/45 (51%) patients in complete response and 24% in partial response; one patient had stable lesions and 1 patient presented progressive disease. The overall response rate was 81% for T3 patients, 61% for T4, 79% for N1 and 70% for N3. The complete response rate was 67% for T3 and 28% for T4. Sixty-four percent of N1 patients and 41% of N3 had a complete response. The 5-year actuarial overall survival was 37% for T3 and 44% for T4 (P = 0.84). Patients with clinically abnormal lymph nodes that were pathologically negative (N1) presented a 5-year survival of 63%. Patients with pathologically positive lymph nodes (N3) experienced a 5-year survival rate of 32% (P = 0.040). CONCLUSIONS: TSEB provides an excellent quality of life by reducing itching and discharge from the skin. Patients with more advanced disease may be treated and cured by the addition of photon beams in combination with TSEB. A selection of patients with advanced skin disease and regional extension may be cured by a combination of TSEB and photon beam irradiation. The regional treatment allows the use of electrons after the reduction of the plaques or thick tumors and a prophylactic irradiation of the adjacent nodal area.

Adult↗
PubMed2000

Clinical impact of dosimetry quality assurance programmes assessed by radiobiological modelling of data from the thermoluminescent dosimetry study of the European Organization for Research and Treatment of Cancer.

The European Organization for Research and Treatment of Cancer (EORTC) Radiotherapy Group initiated its mailed thermoluminescence dosimetry (TLD) programme in 1986. The aim of the present study was to evaluate the clinical relevance of variations in beam output detected in the period 1993 to 1996. A total of 140 beam outputs were checked (26 for cobalt-60 units and 114 for linear accelerators) in 35 centres. Clinical dose-response data for tumour control and normal tissue morbidity were used to assess the variation in clinical outcome resulting from variability in beam output. For 75 checked beams with nominal accelerating potentials (n. a.p.) of 6 MV or less the mean ratio, +/- standard deviation (S.D.) of measured to stated output was 1.004+/-0.020. For 65 beams with n. a.p. of 8 MV or more, the ratio was 1.009+/-0.021. Even with this relatively high level of precision, broad distributions of estimated tumour control or normal tissue morbidity were found. In the 10% of the beams with the most pronounced underdosage, the loss in tumour control probability was estimated at 7-8 percentage points. Likewise, in the 10% of the beams with the most pronounced overdosage, the increase in mild/moderate morbidity was 19-22 percentage points. For severe morbidity the same beams raised the estimated incidence of severe complications from 5% to 9-10%. An estimation of the loss of uncomplicated cure probability was about 1% for both high and low energy beams. Sequential mailings considerably improved the uniformity of clinical outcome. We conclude that small deviations in beam output may lead to clinically important variations in outcome. Substantial reductions in the variation between measured and stated output can be achieved by sequential mailings. Mailed TLD checks should be an integral part of a continuously ongoing quality assurance activity in radiotherapy.

Dose-Response Relationship, Radiation↗
PubMed2000

[Assessment of the use of electronic portal imaging].

Improvement in the accuracy of the positioning of the patient during external irradiation is one of the most important issues of the last decades, due to the detrimental impact of the misplacements on treatment outcome. Since 1990, the evolution of the technologic environment has led to a full integration of the portal imaging devices into linac technology. It offers a real on-line verification tool for "high-dose, high-accuracy" treatments. This overview based upon data from the literature describes the different types of imaging devices, the strategies of use and the results obtained. It also considers the use of imaging devices as an in vivo dosimeter.

Humans↗